The Relationship Between Lymphangiogenesis and Liver Regeneration After Partial Hepatectomy in Cholestatic Mice.

Abstract

Background: The mechanisms of lymphangiogenesis in the cholestatic liver after partial hepatectomy (PH) remain unclear. We aimed to demonstrate the relationship between lymphangiogenesis and liver regeneration after partial hepatectomy in the cholestatic liver. Methods and Results: C57BL/6 mice were subjected to 70% partial hepatectomy only (PH group, n = 20) and 70% partial hepatectomy with temporary common bile duct (BD) obstruction by clipping (BD+PH group, n = 20). Five mice per group were sacrificed at 1, 3, 5, and 7 days after the procedure. The liver function was examined by blood tests, and the liver regeneration rate was assessed by body weight and liver weight. Immunohistochemical staining of lymphatic vessel endothelial hyaluronan receptor-1 (LYVE-1) showed liver lymphangiogenesis. The gene expression of lymphangiogenesis-associated factors (e.g., vascular endothelial growth factor receptor-3 [VEGFR-3]) was examined by a real-time polymerase chain reaction. The liver function in the BD+PH group was worse than that in the PH group on postoperative day 1 (POD1) (aspartate aminotransferase: 6528 ± 1641 U/L vs. 2741 ± 368 U/L, p < 0.05, alanine aminotransferase: 4160 ± 1255 U/L vs. 2315 ± 357 U/L, total bilirubin: 1.36 ± 1.16 mg/dL vs. 0.09 ± 0.01 mg/dL), and the liver regeneration rate in the BD+PH group was worse on POD7 (4.57% vs. 5.91%, p < 0.05). The LYVE-1 expression in Glisson's capsule peaked on POD5 and POD7 in the PH and BD+PH groups, respectively. The peak gene expression of VEGFR-3 in the BD+PH group was delayed in comparison with the PH group. Conclusions: Lymphangiogenesis after partial hepatectomy in the cholestatic liver was suggested to be delayed due to impaired liver regeneration and the late expression of VEGFR-3.